It is recognized in the prior art that utilization of a relatively strong winding spring in the retractor results in a somewhat annoying amount of shoulder belt load across the chest of a seated occupant. It is therefore desirable to provide means for preventing belt winding rotation of the reel by the windup spring so as to relieve the belt tension across the chest of the occupant by introducing slack into the belt.
One such prior seat belt retractor is disclosed in U.S. Pat. No. 4,023,746 issued to Joseph J. Magyar. According to that patent a control disc and a blocking disc are clutched to the reel for rotation therewith and cooperate to control movement of a pawl between positions of engagement and disengagement relative a ratchet wheel attached to the reel. In general, one of the discs is a control disc which controls movement of the pawl between a position engaging the ratchet teeth to prevent reel rotation in the winding direction by the winding spring and a disengaged position permitting reel rotation. The other disc is a blocking disc which is effective to selectively capture and hold the pawl in the disengaged position to thereby deactuate the winding prevention mechanism and restore the winding bias of the spring.